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排序方式: 共有177条查询结果,搜索用时 15 毫秒
1.
无界区域R1上推广的B-BBM方程的整体吸引子 总被引:4,自引:0,他引:4
本文研究了无界区域R^1上推广的B—BBM方程的长时间动力学行为,证明了该方程整体吸引子的存在性. 相似文献
2.
FD—TD在分析FSS中的应用 总被引:3,自引:0,他引:3
本文讨论了用FD TD分析FSS的有关问题,提出了一种适合于在任意入射角情况下分析FSS的有效吸收边界条件,分别以单层、双层FSS为例进行了计算.数值结果和矢量模式法、谱域法的结果非常一致. 相似文献
3.
超短脉冲光电导开关的全波分析 总被引:4,自引:1,他引:3
本文采用时域有限差分法直接求解包含传导电流的三维麦克斯韦方程组,对超短脉冲光电导开关进行全波分析,分析中考虑了静电场影响,采用了比较精确的光电导数学模型。本文还讨论了开关输出信号的模式组成和激光脉冲能量、脉宽对开关性能的影响,并给出了光电导开关响应在不同时刻的三维图形。 相似文献
4.
Affine semigroups are convex sets on which there exists an associative binary operation which is affine separately in either variable. They were introduced by Cohen and Collins in 1959. We look at examples of affine semigroups which are of interest to matrix and operator theory and we prove some new results on the extreme points and the absorbing elements of certain types of affine semigroups. Most notably we improve a result of Wendel that every invertible element in a compact affine semigroup is extreme by extending this result to linearly bounded affine semigroups. 相似文献
5.
Recently, GaAs-based BIB detector has attracted a lot of attention in the area of THz photovoltaic detection due to potential application values in security check and drug inspection. However, the physical mechanisms involving in carrier transition and transport are still unclear due to the poor material quality and immature processing technique. In this paper, the dark current and THz response characteristics have thus been numerically studied for GaAs-based blocked-impurity-band (BIB) detectors. The key parameters and physical models are constructed by simultaneously considering carrier freeze-out and impurity-band broadening effects. Roles of blocking layer and anode bias in processes of impurity-band transition and transport are intensively investigated, and the results can be well explained by numerical models. It is demonstrated that the effective electric field for the detector is only located in the absorbing layer, and can determine to a large extent the magnitude of the dark current and THz response. While the blocking layer not only can suppress dark current but also can attenuate responsivity due to its electric-field modulation effect. 相似文献
6.
7.
In this paper, we investigate the use of ultra weak variational formulation to solve a wave scattering problem in near field optics. In order to capture the sub-scale features of waves, we utilize evanescent wave functions together with plane wave functions to approximate the local properties of the field. We analyze the global convergence and give an error estimation of the method. Numerical examples are also presented to demonstrate the effectiveness of the strategy. 相似文献
8.
Hyun Ho Lee 《Journal of Functional Analysis》2011,260(1):135-145
In this paper we generalize the notion of essential codimension of Brown, Douglas, and Fillmore using KK-theory and prove a result which asserts that there is a unitary of the form ‘identity + compact’ which gives the unitary equivalence of two projections if the ‘essential codimension’ of two projections vanishes for certain C∗-algebras employing the proper asymptotic unitary equivalence of KK-theory found by M. Dadarlat and S. Eilers. We also apply our result to study the projections in the corona algebra of C(X)⊗B where X is [0,1], (−∞,∞), [0,∞), and [0,1]/{0,1}. 相似文献
9.
夏新仁 《电子信息对抗技术》2003,18(5):37-40
从电磁场理论出发,推导出了电磁波以任意角入射时雷达吸波材料的反射系数公式。同时,给出了计算曲线的例子,通过实例计算分析了电磁波的入射角、极化状态等对隐身效果的影响。为雷达吸波材料的计算机辅助分析和设计提供了基础。 相似文献
10.
数字微波共面带线非线性终端瞬态特性模拟及分析 总被引:1,自引:0,他引:1
用FD-TLM法对高速数字微波共面带线端接电阻及非线性终端──半导体二极管时的瞬态响应特性的模拟及分析,并提出一种适用于处理传输线结构终端吸收边界问题的简单、实用的方法。 相似文献